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Dvila, Mara Celeste

Assessment of The Volunteer Process Model in Environmental Volunteers

Interamerican Journal of Psychology, Vol. 43, Nm. 1, 2009, pp. 181-186

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R. Interam. Psicol. 43(1), 2009

Revista Interamericana de Psicologa/Interamerican Journal of Psychology - 2009, Vol. 43, Num. 1 pp. 181-186

181ARTICU

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1 Address: Complutense University of Madrid, Social Psychology

Department, Faculty of Political Science and Sociology, Campus de

Somosaguas, s/n, Madrid, Spain, 28223. Phone: +34 91 394 27 66;

Fax: +34 91 394 30 29.E-mail: [email protected].

Assessment of The Volunteer Process Model in Environmental Volunteers

Mara Celeste Dvila1

Complutense University of Madrid, Spain

Abstract

Most of the explanatory models of volunteerism have focused on the study of assistantial volunteerism

and have not verified whether their results could be generalized to other types of volunteerism. The

purpose of this work is to verify the validity of the Volunteer Process Model in environmental volunteers.

Therefore, a field study of 140 environmental volunteers is presented in which the antecedents and

experiences of volunteerism are used to predict duration of service over one year. In general, the results

obtained indicate that this model does not explain sustained environmental volunteerism adequately.

Keywords: Organizational behavior; prosocial behavior; sustained volunteerism.

Anlisis del Modelo del Proceso del Voluntariado en Voluntarios Ambientales

CompendioLa mayora de los modelos explicativos del voluntariado se han centrado en el estudio del voluntariado

asistencial y no se ha comprobado si estos modelos podran ser generalizados a otros tipos de voluntariado.

El propsito de este trabajo es analizar la validez del Modelo del Proceso del Voluntariado en voluntarios

ambientales. Con este objetivo se llev a cabo un estudio de campo en el que se evaluaron los antece-

dentes y las experiencias de voluntariado de 140 voluntarios ambientales para predecir su permanencia

en la organizacin voluntaria a lo largo de un ao. En general, los resultados obtenidos muestran que el

modelo estudiado no explica adecuadamente la permanencia del voluntariado ambiental.

Palabras clave: Conducta organizacional; conducta prosocial; permanencia del voluntariado.

Volunteerism is a social phenomenon that consists

basically of devoting time and work to various causes.

In the last few years, its expansion and social acceptancehave increased to such an extent that governments of

very diverse states have assimilated it as an indispensable

pillar to provide various services.

This kind of behavior is so important that its specific

study has awakened the interest of social scientists.

Psychosocial research has studied this phenomenon from

various viewpoints. Thus, some investigations focus on

the identification of the variables that differentiate

volunteers from nonvolunteers in an attempt to clarify

the determinants that lead an individual to decide to

become a volunteer, whereas others attempt to identify

effective predictors of sustained volunteerism (Clary &

Snyder, 1991).

Many different variables have been analyzed, although

not all have received the same attention. Smith (1994)

carried out a bibliographic review between 1975 and

1992 and identified five categories of variables: (a) con-

textual variables (size of residential community, nature

of the volunteer organization or group, etc.); (b) social

background variables (education, gender, etc.); (c) perso-

nality variables (disposition to be helpful, extraversion,

etc.); (d) attitudinal variables (sympathy for the groupreceiving the service, etc.); (e) situational variables

(relations with other people, etc.).

Vecina (2001) included a sixth category: volunteer

motivations, to which Smith (1994) only referred indi-

rectly when describing the attitudinal variables.

Omoto and Snyder (2002) proposed other more

exhaustive categories based on level of analysis (agency,

individual volunteers, social system) and stages of the

volunteer process (antecedents, experiences, consequen-

ces), but these categories can be gathered under Smiths

categories.

Smiths (1994) review and Omoto and Snyders

(2002) categories showed that volunteerism is a multi-

determined phenomenon and, given its complexity,

theoretical models should be designed to organize the

importance and relative influence of the determinants

of its explanation. Penner (2004) proposed that a full

understanding of sustained volunteering requires a con-

sideration of situational, dispositional and structural

variables and must have a temporal and dynamic com-

ponent as well.

Towards the mid nineties, new explanatory models

of initiation and development of volunteer activity began

to be published. Despite the fact that there are other

explanatory models, Omoto and Snyders (1995) model

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is perhaps the most well known. This model covers the

phases through which volunteers working with AIDS

go and predicts the duration of their sustained volun-

teerism and the attitude change that comes about as a

result of their activity. The authors distinguished threepoints in this process, and in each one, they identified a

series of variables as determinants: (a) The antecedents

of volunteer behavior provide information about the

factors that lead people to become volunteers: disposition

to be helpful (personality attributes), motivations and

social support. The dispositional variables play a more

important role because there are few situational res-

trictions in the initial decision to become a volunteer.

In this sense, the model places special emphasis on

motives and needs (Penner & Finkelstein, 1998). (b)

Volunteerism experience refers to the experiences that

may promote or deter continuing involvement. Omoto

and Snyder (1995) focused on two factors: satisfaction

with volunteer activity and organizational integration.

(c) The consequences for the volunteers, the receivers,

the organization and society in general were also takeninto account by Omoto and Snyder (1995), although, in

fact, they were only interested in predicting the following

ones: Length of service as a volunteer and attitude

change towards the target population of the intervention.

Upon testing their model (see Figure 1), they found

that: motivation had a direct and positive influence on

length of service, satisfaction was related to longer length

of service, social support had a direct and negative

relationship with longevity of service, and the helping

disposition construct had a direct and positive influence

on satisfaction and on organizational integration.

Subsequently, other theoretical models derived from

Omoto and Snyders model have been developed: The

main contribution of Davis, Hall, and Meyer (2003) is

the introduction of subjective experiences while volun-

teering; and the main contribution of Vecina (2001) is

the integration of more psychosocial variables (organi-

zational conflict and support, for example).

From another theoretic perspective, Piliavin and

associates (Callero, Howard, & Piliavin, 1987; Grube& Piliavin, 1996; Piliavin & Callero, 1991) developed

the Role Identity Model of Volunteerism. In this model,

the concept of role identity is important to explain the

continuity of volunteerism. Wilson and Musick (1997)

presented a model in which both volunteering and

informal helping are predicted from demographic

variables and various types of capital (human capital,

social capital and cultural capital).

Among the most recent models, we highlight the

conceptual model of Penner (2004) of the initial deci-

sion to volunteer, or his conceptual model of sustained

volunteerism (Penner, 2002), the innovative model of

Hart, Atkins and Donnelly (2004, see Penner, Dovidio,

HELPING PERSONALITY

MOTIVATIONS

SOCIAL SUPPORT

INTEGRATION

SATISFACTION

Figure 1. Omoto and Snyders (1995) volunteer process model

Piliavin, & Schroeder, 2005),which attempts to integrate

both sociological and psychological approaches to

volunteering, and three-stage model of volunteers

duration of service (Chacn, Vecina, & Dvila, 2007)

to explain the different factors that predict the duration

of service over short or long periods of time.

In contrast, despite the differences there may be

among the models developed up to the present, most of

them were designed to explain sustained volunteerismin the socio-health area. In the research on volunteerism,

very few studies have been carried out with other types

of volunteerism, such as, for example, environmental

volunteerism. From volunteerisms research in Spain,

we highlight the basic model (Dvila & Chacn, 2004,

2007) to explain sustained volunteerism in any type of

volunteerism.

Recent research has shown that socio-assistantial

volunteers and environmental volunteers present statis-

tically significant differences in very diverse variables

that are relevant to sustained volunteerism (Dvila,

2003): motivations, organizational variables (activity

characteristics, relationship with other volunteers and

DURATION

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tive, values, career, social, understanding, and enhan-

cement. The total reliability of the scale was .92, and

the reliability interval for the subscales was .61 - .90.

Organizational Commitment. Organizational com-

mitment was assessed by the following measures: (a)Some questions and responses format used by Omoto

and Snyder (1995) to measure the construct they called

organizational integration: their acceptance of the

philosophy, goals, and purposes of organization; their

willingness to recruit new volunteers for the orga-

nization; and the extent to which they would like to

take on additional assignments at the organization. (b)

The reduced version of the Organizational Commitment

Questionnaire (OCQ) by Mowday, Steers, and Porter

(1979), adapted to the Spanish population and volun-

teerism by Dvila and Chacn (2003a, 2003b). This

questionnaire has 9 items with a 7-point Likert-type res-ponse format, ranging from 1 (completely disagree) to

7 (completely agree). The internal consistency reliability

was 0.88.

The following variables were assessed by means of

similar measurement instruments as those used in the

original study by Omoto and Snyder (1995).

Social Support. The measures included were about

perceived availability of support: (a) the degree of

emotional support that he/she receives from people who

know about his/her volunteer activity: family, friends, a

partner, or fellow workers (evaluated on a 7-point scale);

(b) the degree of general support for the development ofthe volunteer activity that he/she receives from signi-

ficant others (evaluated on a 7-point scale)

Satisfaction. The volunteers job satisfaction was

evaluated by: (a) the respondents rated (1 = not at all, 7

= extremely) their experiences as volunteers on the

following nine dimensions: Satisfying, rewarding, exci-

ting, interesting, disappointing, enjoyable, challenging,

important, boring; (b) volunteers also used a 7-point

scale (1 = strongly disagree, 7 = strongly agree) to

rate their agreement with a general satisfaction item

(Overall, I am satisfied with my experience as a

volunteer).

Total Duration of Service. Omoto and Snyder (1995)

assessed sustained volunteerism in the organization by

adding the previous sustained service and the length of

service during the follow-up periods.

Whenever possible, we used the same instruments

as those originally employed, but in some cases, we

decided that other instruments were better adapted to

the requirements of the present study or that they would

improve the prediction of the theoretical constructs.

ProcedureThe conditions of the questionnaire administration

were agreed upon with each organization to cause the

least possible interference in its habitual functioning.

staff, organizational support, organizational conflict,

economic costs derived from volunteer activity, super-

vision, training and incentives received), and orga-

nizational attitudes (satisfaction and job involvement).

In addition, according to the cognitive typology deve-loped by Chacn and Dvila (2001), people clearly

differentiate environmental volunteerism and socio-

assistantial volunteerism.

A review of studies of environmental volunteerism

can be found in Martnez and McMullin (2004), and

Rayan, Kaplan and Grese (2001).

According to these important differences observed,

we wondered whether the models developed so far,

models designed chiefly to account for socio-assistantial

volunteerism, are useful to explain environmental volun-

teerism. The aim of the current study is to determine if

Omoto and Snyders (1995) model can be generalizedto environmental volunteerism. The analysis will focus

on the causal relationships.

Method

ParticipantsIn this study, 140 volunteers belonging to 6 Spaniards

nongovernmental environmental organizations parti-

cipated.

The volunteers carried out various activities: project

management, clerical jobs, document classification,

medical treatment, bird census, territory observation,care of animals in shelters, restoration of shelters,

reforestation jobs, and environmental education.

The sample was composed by 73.6% men and 26.4%

women. Their ages ranged between 17 and 67 years,

with a mean age of 33 years and a standard deviation of

8.5 years. Regarding educational level, 7.1% had

elementary studies, 35% secondary studies, and 57.9%

university studies.

InstrumentsThe following instruments were used to assess the

constructs included in each of the explanatory models:

Disposition to be Helpful. To measure this cons-

truct, we used the Emotional Empathy Questionnaire

(Mehrabian & Epstein, 1972), comprised of 33 items

with a 9-point Likert-type response scale. The internal

consistency reliability was 0.73.

Motivations. To study motivations that lead people

to become volunteers, we used the Volunteer Functions

Inventory (VFI) of Clary et al. (1998), adapted to the

Spanish population and to environmental volunteerism

by Dvila and Chacn (2003a, 2003b). This instrument

consists of 30 items, to which participants respond on

a 7-point scale ranging from 1 (not important) to 7

(extremely important). It includes 6 subscales: Protec-

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In some cases, a representative of the organization

distributed the questionnaires and collected them later

on. In other cases, the representative provided a list of

the volunteers addresses, so we could send them the

questionnaire along with a pre-paid envelope for itsreturn. Lastly, in other cases, the representative took

charge of sending the questionnaire by e-mail to the

volunteers, to be returned either by normal mail, e-mail,

or fax to the organization representative or to the

research representative.

Although these different data collection procedures

could have potentially affected the volunteers res-

ponses, we sought to keep collaboration rates as high

as possible by adjusting to the requirements of the

organizations.

After collecting the measurements, two telephone

follow-ups were carried out to determine whethervolunteers remained in the NGO: at 6 months and at 12

months.

Thus, out of the 140 volunteers who constituted the

sample: (a) at the first follow-up, 22 volunteers had

dropped out of the organization; (b) at the second follow-

up, 4 volunteers had dropped out.

Data AnalysisTo verify the predictive power of Omoto and Snyders

(1995) model in environmental volunteers, structural

equation models were employed (AMOS 4.0 computer

program).

Results

The goodness-of-fit indexes obtained for the model

of Omoto and Snyder (1995) in the sample of

environmental volunteers are shown in Table 1.

Omoto and Snyders (1995) model is graphicallyrepresented in Figure 2, as well as the standardized

regression weights of the most important relationships

and the percentages of explained variance of each

construct. In addition, the observed variables that were

used for the configuration of the constructs can also be

examined.

In Omoto and Snyders (1995) model, (321, N=

140) = 736.130,p = .000, so it can be assumed that the

differences between the effective and the foreseen

matrixes were significant, and, therefore, the fit of the

model is not acceptable (see Table 1).

When reviewing other absolute goodness-of-fitindexes (GFI, RMSEA), and indexes of incremental fit

(AGFI, NFI, IFI) for Omoto and Snyders (1995) model,

we found that none of them presented values that could

be considered acceptable (see Table 1). GFI, AGFI, NFI

and IFI have a range of 0.0 to 1.0, with values closer to

1.0 indicating better fitting models. RMSEA with a value

of 0.0 indicates that the model exactly fits the data, but

values between 0.0-0.08 are considered acceptable (Hair,

Anderson, Tatham, & Black, 1999).

The regression weights and explained variance shown

in Figure 2 confirm the poor fit of the model in environ-

mental volunteers. The only relationships hypothesized

by the model that were significant were between empathy

Table 1

Goodness-of-fit Indexes Obtained

STUDIES df p GFI RMSEA AGFI NFI IFI

Omoto & Snyder (1995) 147.010 96 .001 .860

Environmentalvolunteers 736.130 321 .000 .719 .096 .669 .474 .615

and satisfaction (CR = coefficient/SE= 3.797,p < .05),and between empathy and organizational integration

(CR= 2.324, p < .05). None of the remaining hypo-

thesized relationships was significant. Moreover, the

percentages of explained variance of each construct were

low, and not even 7% of the variance of the total duration

of sustained volunteerism was accounted for.

Discussion

In general, the results obtained show that Omoto

and Snyders (1995) model does not explain sustained

environmental volunteerism adequately. The fit to theempirical data cannot be considered acceptable, the

percentages of explained variance of satisfaction, inte-

gration, and total duration of service are very low, and

some relationships between constructs are not significant.

Motivations had a positive influence on service

duration, but it was not significant; satisfaction was

related to longer service duration, but it was neither

positive nor significant; and social support had a direct

and negative relationship with service duration, but it

was not significant. Ultimately, the only significant

relationships were between empathy (concerning the

helping disposition construct) and satisfaction, and

between empathy and organizational integration.

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The lack of support for the model confirms that it

cannot be generalized to another type of volunteerism.

However, the results found do not question the validity

of the model for AIDS volunteerism, as the model was

developed for this type of volunteerism. In the study by

Omoto and Snyder (1995), the volunteers carried out

activities involving a high emotional demand, and,

obviously, the environmental sample performed activities

that differ enormously from those of the former study.

Thus, the poor fit of the former model may be due to the

fact that it was designed and adapted to volunteers with

certain characteristics not shared by those who partici-

pated in this present research.

The lack of support for the model may also be par-

tially due to differences in the methodology employed

to collect the data and to the specification of the varia-

bles observed in the model, as well as cultural diffe-

rences. The most important differences are described

more extensively in the following paragraphs.

Some of the variables observed included by Omoto

and Snyder (1995) to determine latent constructs could

not be included in the current study, either because it

was impossible to find measurements with appropriate

psychometric qualities or because, when using some of

these measurements, unacceptable estimations were

Figure 2. Omoto and Snyders (1995) model. Standardized regression of the most important relationships, covariances, and the percentages of ex-

plained variance

obtained that invalidated the analyses of the data. In the

case of motivations, a more up-to-date instrument was

used (Clary et al., 1998).

Moreover, we had to select instruments that were

easily adaptable to environmental volunteerism, because

practically all the instruments used in the study of

volunteerism are designed to assess socio-assistantial

volunteerism, and in some cases, we had to add other

measures for the best prediction of the constructs, as in

the case of organizational integration.

In addition, the procedure used to gather data was

slightly different from those used in the original research.

Omoto and Snyder (1995) combined information from

volunteers self-reports and from agency records to carry

out the follow-ups. Also, in the current study, the total

follow-up had a 1-year duration, whereas in the former

study, it lasted 2 years.

Lastly, it should be remembered that this study focused

on the analysis of causal relationships, and this may have

reduced the explanatory capacity of the model, because

covariate relationships were not included. But we think

that the general results would not be very different if theses

relationships had been taken into account.

The results indicate the need for the study of volun-

teerism to be sufficiently sensitive to the peculiarities of

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each type of volunteerism and, hence, to the risk of

overgeneralization of some findings. Specifically, not

only the differences observed in the fit of the explana-

tory model, but also the lower percentages of explained

variance reveal the idiosyncrasy of environmentalvolunteerism.

We also would like to emphasize the need to study

environmental volunteerism and to design models that

explain the permanence of this type of volunteers. The

number of environmental volunteers and the number of

environmental organizations have increased exponen-

tially in the last years, and the psycho-social studies of

environmental volunteerism are still relatively few.

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Maria Celeste Dvila. Ph.D. in Psychology and lecturer in Complutense University of Madrid, Spain.

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